Field of the Invention
The present disclosure generally relates to electronics and, more particularly, to an electronic apparatus having a capacitive touch panel, a control method thereof, and a storage medium.
Description of the Related Art
In recent years, an increased number of electronic apparatuses such as a smart phone and a digital camera are available each having a touch panel by which a touch operation of a finger, for example, can be two-dimensionally detected. Various types of touch panel are available such as pressure sensitive, capacitive and optical touch panels and can determine the presence/absence of a touch input by comparing a touch sensor output value with a predetermined threshold value. If a touch input is present, the touch panel determines touch position coordinates from one or more touch sensor output values.
A capacitive touch panel detects a touch operation by comparing a capacitance value being a touch sensor output or an amount of change therein with a predetermined threshold value. The capacitance value varies in accordance with a touch area of a touch input. Normally, a touch position can be determined by using detected capacitance values from a plurality of adjacent sensors. However, because one of the adjacent sensors is not provided in an end of a sensor region of the touch panel, a touch operation including a touch off a sensor region if any may result in a calculated touch position coordinates different from actual coordinates of a touch position intended by a user, reducing the touch positional accuracy.
Against the problem, Japanese Patent Laid-Open No. 10-20992 discloses a technology including selecting, as an alternative to the other adjacent sensor, an end sensor in a side of an operating region opposite to a touched side of the sensor region and calculating the actual touch position coordinates.
The technology in the past disclosed in Japanese Patent Laid-Open No. 10-20992 may not achieve highly accurate calculation of a touch position for a touch at an end of a sensor region. A touch onto an end of a sensor region exhibit a substantially constant sensor output value independent from how a user touches. Thus, the contribution ratio of the calculation of touch position coordinates is also independent from a small difference in end touch position between an end side, a center and an opposite end side on an end sensor, for example, and the same result can be obtained from the calculation of the touch position coordinates. In other words, the accuracy reflecting a difference in touched position may not be achieved.